The present invention relates generally to a pattern recognition method and system for determining a state-of-health (SOH) of a battery.
A vehicle's electrical power supply system must support a plurality of vehicle functions that operate on electrical energy. Such functions include normal vehicle operation devices and safety related devices such as rear window defogger, anti-lock braking/stability systems, lighting systems, etc. Additionally, the vehicle's electrical power supply system supports comfort, convenience, and entertainment devices. Some examples include air conditioning, heated seats, video/audio systems, and accessory outlet convenience devices. Moreover, with the advent of new X-by-wire technologies (e.g., steer-by-wire, brake-by-wire, etc.), even more electrical power is being demanded of the vehicle's electrical power system.
The increasing use of electrical devices as described above directly affects the drain on the vehicle battery, and more so the battery's state-of-health since acceleration of battery aging has a direct correlation with the frequency of use of such devices, which use the vehicle battery as their power source.
Therefore, on-board battery status systems attempt to determine when a battery may fail. On-board vehicle state-of-health information is typically derived based on a deterministic mathematical model; however, in many applications, it is very difficult to obtain such an accurate physics-based system model.